Which tool is commonly used to represent the relationships between project activities?

A network diagram is commonly used to represent the relationships between project activities because it visually displays the sequence and dependencies among tasks. This representation allows project managers to understand how activities relate to each other, which is crucial for scheduling and resource allocation. In a network diagram, activities are represented as nodes, and the dependencies between them are shown as directed arrows. By illustrating these relationships, the diagram helps in identifying the critical path, which is essential for determining the project timeline and ensuring that key tasks are prioritized.

In contrast, a Gantt chart focuses on the timeline of project tasks and visually represents start and end dates but does not explicitly show how tasks are interrelated. Resource allocation charts illustrate how resources are distributed across tasks but lack a focus on task relationships. Budget spreadsheets, while important for financial planning, do not convey information about activity relationships. Hence, the network diagram is the most effective tool for visualizing the connections between various project activities.